Recent years have witnessed a significant rise in the per capita consumption of poultry. This increase has been accompanied by a decrease in the consumption of beef. Much of this increase in poultry consumption (generally chicken) can be attributed to a heightened awareness on the part of the consumer of the need to eat foods which are lower in fats, particularly animal fat. This has quite naturally lead to an increase in the consumption of poultry, which is lower in harmful fats than beef. Much of the fat contained in poultry is situated subcutaneously, i.e., at or beneath the skin. By removing the skin, one further reduces the quantity of fat and the caloric content of an already healthy food substance.
Originally, those wishing to prepare meals utilizing skinless chicken parts were dependent upon manual labor to remove the chicken skin. However, in time, machines were developed to automate this process so that today one can purchase machine deskinned chicken parts at the supermarket. Such machines must be economical for use in a mass production setting, and preferably should be flexible enough to handle a full range of chicken or other poultry parts. In addition, while being rapid and effective in separating skin from meat, such machines must not overly damage the meat itself, for this reduces the marketability of the product.
Finally, and of great importance, such a machine must be designed so that it is easy to clean. Poultry is a well known source of salmonella and other bacterial contaminants. Salmonella is a common contaminant carried in the gut of most poultry. During the slaughtering and dismemberment of chickens and other foul, the viscera unavoidably make contact with the surface of the bird, thereby contaminating the skin and other exposed parts. By removing the chicken skin, one at least partially removes some of the salmonella. However, this presents a special problem with respect to maintaining a deskinning apparatus in proper hygienic condition. Because salmonella is largely a phenomena of surface contamination (i.e., outside of the digestive tract, it is most commonly found on the skin), any apparatus that removes the skin must be designed so that it can be kept clean. Structural features of a deskinning machine which are of little import with respect to the purely mechanical action of deskinning can take on great importance when considered in view of the need to maintain a clean work environment.
U.S. Pat. No. 4,723,339 to Van de Nieuwelaar et al. teaches a deskinning apparatus which uses transverse pinch roles 10a and 10b with helical teeth. These helical rolls counterrotate and are used to grip and tear skin from the underlying tissue. However, this device is not suitable for use on individual parts, and requires separate structure to move the chicken across the rolls. The patent to Hill, U.S. Pat. No. 4,459,721 (hereby incorporated by reference), teaches a device to deskin individual chicken parts. However, it relies on blind bearing blocks separated by a narrow gap and a shear section for separating the skin from the chicken, both of which are very difficult to clean. This may present a heightened risk of contamination from salmonella and other microbes as noted above.
This invention is directed towards the further refinement of a versatile, economical chicken and other poultry deskinning apparatus that is easy to clean and effective to use.